420 research outputs found
Evaluation of the potential for energy saving in macrocell and femtocell networks using a heuristic introducing sleep modes in base stations
In mobile technologies two trends are competing. On the one hand, the mobile access network requires optimisation in energy consumption. On the other hand, data volumes and required bit rates are rapidly increasing. The latter trend requires the deployment of more dense mobile access networks as the higher bit rates are available at shorter distance from the base station. In order to improve the energy efficiency, the introduction of sleep modes is required. We derive a heuristic which allows establishing a baseline of active base station fractions in order to be able to evaluate mobile access network designs. We demonstrate that sleep modes can lead to significant improvements in energy efficiency and act as an enabler for femtocell deployments
Green Cellular Networks: A Survey, Some Research Issues and Challenges
Energy efficiency in cellular networks is a growing concern for cellular
operators to not only maintain profitability, but also to reduce the overall
environment effects. This emerging trend of achieving energy efficiency in
cellular networks is motivating the standardization authorities and network
operators to continuously explore future technologies in order to bring
improvements in the entire network infrastructure. In this article, we present
a brief survey of methods to improve the power efficiency of cellular networks,
explore some research issues and challenges and suggest some techniques to
enable an energy efficient or "green" cellular network. Since base stations
consume a maximum portion of the total energy used in a cellular system, we
will first provide a comprehensive survey on techniques to obtain energy
savings in base stations. Next, we discuss how heterogeneous network deployment
based on micro, pico and femto-cells can be used to achieve this goal. Since
cognitive radio and cooperative relaying are undisputed future technologies in
this regard, we propose a research vision to make these technologies more
energy efficient. Lastly, we explore some broader perspectives in realizing a
"green" cellular network technologyComment: 16 pages, 5 figures, 2 table
Technical, financial and environmental evaluation of 4G long term evolution: advanced with femtocell base stations
Recent advances in mobile communication technology have allowed for considerable
growth both in traffic and user numbers. However, in order to maintain acceptable quality of
experience and service levels with increasing network capacity requirements, a mobile
communications operator is challenged with high investment costs and high operating costs.
Cost effectiveness and environmental sustainability are two major factors a mobile
telecommunications operator must take into account in order to maintain its network planning
techniques ready for the accelerated growth of traffic in future mobile networks. With the
incoming LTE-Advanced system and with the increasing popularity of femtocells, it becomes
necessary to evaluate and quantify the economic viability and sustainability of this new type
of base station when used as a standalone deployment option, as well as when used in a two-tier network.
Therefore, different cases were used with a deployment method based on capacity
used with a varying non-uniform traffic distribution in order to assess the future resistance
and flexibility of this proposed solution. A comparison was made between macro cell
coverage only, full femtocell coverage and a two-tier joint solution.
Our study has concluded that for low capacity demands, the best approach is a two-tier network with femtocells used for indoor backhaul. A joint solution also allows for the
cost-effective resolution of indoor coverage issues. According to our future capacity
requirements projected, it has been concluded that a full femtocell deployment, by far, the
most economically viable option.
A method for the quantification and suppression of carbon emissions due to energy
consumption is also proposed, through which we studied and estimated the price for the
achievement of a zero carbon emissions network.Os recentes avanços na tecnologia de comunicações móveis têm permitido um
crescimento considerável da indústria, tanto em termos de tráfego como em número de
clientes. No entanto, para conseguir manter uma qualidade de experiência aceitável e com
elevada qualidade de serviço, um operador de comunicações móveis depara-se com elevados
custos de investimento e operação.
A eficácia em termos de custos e a pegada ambiental são dois factores que, entre
outros, um operador de telecomunicações móveis deve ter em conta de modo a manter as suas
técnicas de planeamento de rede preparadas para o acelerado crescimento do tráfego nas redes
móveis do futuro. Com a chegada próxima do LTE-Advanced e com a crescente popularidade
de femtocells, torna-se necessário avaliar e quantificar a viabilidade económica e o potencial
de poupança de energia deste novo tipo de estação de base quando utilizado como uma opção
de implantação autónoma, ou quando utilizado para suporte de uma rede de macro células.
Dessa forma, foram dimensionados diferentes casos de implementação baseados nos
requisitos de capacidade. Foi também aplicada uma distribuição de tráfego não-uniforme, a
fim de avaliar a resistência ao futuro e a flexibilidade de aplicação desta solução proposta.
Fez-se uma comparação entre uma implementação apenas com recurso a macro células, uma
implementação feita completamente com recurso a femtocells e uma solução conjunta destes
dois tipos de estação-base.
O estudo concluiu que, para requisitos de baixa capacidade, a melhor implementação
é uma rede de duas camadas, com femtocells utilizadas para o backhaul das ligações indoor.
A solução conjunta permite ainda a resolução eficaz de problemas de cobertura no interior de
edifÃcios. De acordo com a nossa projecção das necessidades futuras de capacidade concluiu-se que a implementação de uma rede apenas com recurso a femtocells é a melhor opção, do
ponto de vista da capacidade, financeiro e ambiental.
Também foi apresentada uma metodologia para quantificar a pegada ambiental
devida ao consumo de energia, através da qual se estudou e estimou os custos associados Ã
implementação de uma rede com pegada ambiental nula
Energy efficiency perspectives of femtocells in internet of things : recent advances and challenges
Energy efficiency is a growing concern in every aspect of the technology. Apart from maintaining profitability, energy efficiency means a decrease in the overall environmental effects, which is a serious concern in today's world. Using a femtocell in Internet of Things (IoT) can boost energy efficiency. To illustrate, femtocells can be used in smart homes, which is a subpart of the smart grid, as a communication mechanism in order to manage energy efficiency. Moreover, femtocells can be used in many IoT applications in order to provide communication. However, it is important to evaluate the energy efficiency of femtocells. This paper investigates recent advances and challenges in the energy efficiency of the femtocell in IoT. First, we introduce the idea of femtocells in the context of IoT and their role in IoT applications. Next, we describe prominent performance metrics in order to understand how the energy efficiency is evaluated. Then, we elucidate how energy can be modeled in terms of femtocell and provide some models from the literature. Since femtocells are used in heterogeneous networks to manage energy efficiency, we also express some energy efficiency schemes for deployment. The factors that affect the energy usage of a femtocell base station are discussed and then the power consumption of user equipment under femtocell coverage is mentioned. Finally, we highlight prominent open research issues and challenges. © 2013 IEEE
Spectrum Sharing for LTE-A and DTT: Field Trials of an Indoor LTE-A Femtocell in DVB-T2 Service Area
(c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.In this paper, we study a particular case which goes a step beyond the previous ones, as it aims at sharing the same frequency band in the same area between long term evolution-advance (LTE-A) and digital video broadcasting-terrestrial second generation (DVB-T2) technologies. Those geographical areas that are not covered because the useful DTT signal is obstructed by the environment or it has a limited coverage by the network design can be called micro-TVWS. We assume that a DVB-T2 transmitter provides coverage for fixed rooftop reception as a primary service, to a building in which a LTE-A femtocell is installed indoors for local coverage, as a secondary service. The results have been obtained by laboratory emulation and validated through field measurements using professional equipment. Our results provide the technical restrictions of the LTE-A femtocell, mainly on the maximum allowable effective isotropic radiated power that could transmit on the DTT band in terms of carrier separation, from co-channel to adjacent band. These results meet the need of spectrum for IMT-Advanced technologies, so spectrum sharing is proposed in this paper as a new solution to make an efficient use of this resource.This work was supported in part by the Ministerio de Educacion y Ciencia, Spain, under Grant "DEFINE5G" TEC2014-60258-C2-1-R and Grant "ARCO5G" TEC2014-56469-REDT, and in part by the European FEDER Funds.MartÃnez Pinzón, G.; Cardona Marcet, N.; GarcÃa Pardo, C.; Fornés Leal, A.; Ribadeneira-RamÃrez, JA. (2016). Spectrum Sharing for LTE-A and DTT: Field Trials of an Indoor LTE-A Femtocell in DVB-T2 Service Area. IEEE Transactions on Broadcasting. 62(3):552-561. https://doi.org/10.1109/TBC.2016.2582338S55256162
Technical advances in the design and deployment of future heterogeneous networks
The trend in wireless communications systems is the enhancement of the network infrastructure with the introduction of small cells, where a specific geographical area is served by low-range, low-power access points. The result is the creation of a heterogeneous topology where macrocells coexist with a variety of small-cell types. In this editorial article we briefly summarize the recent technical advances in the design and deployment of future heterogeneous networks addressed in the papers that compose this special issue. In particular the following aspects are considered: the design of interference and radio resource management algorithms, the analysis of the energy efficiency and power control issues in heterogeneous networks, the concept of coordination in small cell networks, key backhaul aspects of HetNets, deployment issues and overall management strategies.Peer ReviewedPostprint (published version
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